DTC Descriptions

Name Of Code: P0604, P0605, P0613 (11, 13, 16, 17 or 45) - Internal Controller

When Monitored: Whenever the key is in the Run or Run/Start position.

Set Condition: This code is set whenever Transmission Control Module (TCM) senses an internal error.

Theory Of Operation: The TCM is constantly monitoring it's internal processor. If an internal problem is detected, this DTC will be set. This DTC can also be set by a bad ground to the TCM and/or Trans Control Relay. In fact, this DTC is rarely set due to a TCM error, it is usually set by a poor ground.

Transmission Effects: The MIL will illuminate (this DTC can take up to five minutes of problem identification before illuminating the MIL) and the transmission system will default to the Immediate Shutdown routine.

Possible Causes:

TCM ground circuit. (check main ground attachment to engine block)
Relay ground circuit. (check main ground attachment to engine block)
TCM

Name Of Code: P1684 (12) - Battery was Disconnected (Info Only)

When Monitored: Whenever the key is in the Run or Run/Start position.

Set Condition: This code is set whenever Transmission Control Module (TCM) is disconnected from battery power (B+) or ground. It will also be set during the DRBIII® Quick Battery Disconnect procedure.

Theory Of Operation: A battery backed RAM (Random Access Memory) is used to maintain some learned values. When the battery B(+) is disconnected, the memory is lost. When the B(+) is restored, this memory loss is detected by the TCM. The code is set and the learned values are initialized to known constants or previously learned values from EEPROM (Electronic Erasable Programmable Read Only Memory). This results in the re-initialization of some parameters.

Transmission Effects: Loss of trouble code data. The Transmission system will default to the Immediate shutdown routine if power is lost while operating the vehicle. Normal operation is resumed if the power is restored during the same key start.

Possible Causes:

Battery voltage removed from TCM (Fused B+)
TCM disconnected
Dead Battery
Low battery voltage during cranking
Quick Battery Disconnect by DRBIII® or MDS
Bad TCM ground circuit.

Name Of Code: P0891 (14) - Relay Always On

When Monitored: When ignition key is turned from "off" position to "run" position and/or ignition key is turned from "crank" position to "run" position.

Set Condition: This code is set if the Transmission Control Module (TCM) senses greater than 3 volts at the Trans Control Relay Output terminal(s) of the TCM prior to the TCM energizing the relay.

Theory Of Operation: The transmission control relay is used to supply power to the solenoids and pressure switches when the transmission is in normal operating mode. The relay output is fed back to the TCM through pins 16, 17, and 36. It is referred to as "Transmission Control Relay Output". This circuit does not supply power to the TCM, it is only a sense circuit. When the relay is off, no power is supplied to the solenoids and pressure switches, and the transmission is in "limp-in" or "default" mode.

Possible Causes:

Short to voltage in the Transmission Solenoid/TRS Assembly (internal into any solenoid control circuit)
Short to voltage on any solenoid control circuit
Relay contacts stuck together.
Short to voltage in Transmission Control Relay output circuit(s).
Short to voltage in Transmission Relay Control circuit.
Short to voltage on any pressure switch sense circuit.
TCM connector problems.
TCM.

Name Of Code: P0888 (15) - Relay Output Always Off

When Monitored: Continuously

Set Condition: This code is set when less than 3 volts are present at any transmission control relay output (pins 16, 17 or 36) circuits at the Transmission Control Module (TCM) when the TCM is energizing the relay.

Theory Of Operation: The Transmission Control Relay is used to supply power to the solenoids and pressure switches when the transmission is in normal operating mode. The relay output is fed back to the TCM through pins 16, 17, and 36. It is referred to as "Transmission Control Relay Output". This circuit does not supply power to the TCM, it is only a sense circuit. When the relay is off, no power is supplied to the solenoids and pressure switches, and the transmission is in "limp-in" or "default" mode.

After a controller reset (ignition key turned to the "run" position or after cranking engine), the controller energizes the relay. Prior to this the TCM verifies that the contacts are open by checking for no voltage at the switched battery terminals. After the relay is energized, the TCM monitors the terminals to verify that the voltage is greater than 3 volts.

Possible Causes:

Transmission Control Relay (intermittent relay function caused by oxidized or contaminated relay contacts)
Short to ground or open circuit in the transmission control relay output circuit(s)
Short to ground or open circuit in the Transmission Solenoid/TRS assembly
TCM connector problem
Relay connector problem
Relay Ground circuit
TCM Ground circuit(s)
TCM

Name Of Code: P0725 (18) - Engine Speed Sensor Circuit

NOTE: This code is not a Transmission Input Speed Sensor DTC

When Monitored: Continuously with engine running.

Set Condition: This code is set when the engine speed calculated by the Transmission Control Module (TCM) is less than 390 RPM, while the engine speed broadcast by the PCM is greater than 383 RPM. The DTC also sets if the calculated engine speed is greater than 8000 RPM for more that 2.0 seconds.

Theory Of Operation: The TCM uses the crank sensor signal to calculate engine RPM. The TCM uses RPM data from the PCM which is broadcast over the communication bus to determine if the engine is running. The TCM continuously compares calculated engine speed to the engine RPM reported on the bus, by the PCM, so that loss of crankshaft position sensor signal to the TCM will not be misinterpreted as engine not running.

Possible Causes:

Open or short in engine speed sensor circuit. (Crank sensor signal)
TCM connector problems (Crank sensor signal or sensor ground terminals)
Open or short in sensor ground circuit
Low engine idle speed
TCM
PCM.

Name Of Code: P1694 (19) - Bus Communication with Engine Module

When Monitored: Continuously with key on.

Set Condition: If no bus messages are received from the Powertrain Control Module (PCM) for 10 seconds.

Theory Of Operation: The TCM communicates with the PCM using the communication bus. It relies on certain information to function properly. The TCM continuously monitors the bus to check for messages broadcast from the PCM.

Transmission Effects: Delayed 3-4 shifts. No EMCC and early 3-4 shifts for a few minutes after engine is started. Generally poor shift quality.

Possible Causes:

Open or shorted bus circuit
TCM
PCM

Name Of Code: P0706 (28) - Check Shifter Signal

When Monitored: Continuously with the key on.

Set Condition: Any occurrences of an invalid PRNDL code which lasts for more than 0.028 second.

Theory Of Operation: The C1 through C5 (TRS T1, TRS T2, TRS T3, TRS T41, and TRS T42) sense circuits communicate the shift lever position to the TCM. Each circuit is terminated at the transmission with a switch. Each switch can be either open or closed, depending on the shift lever position. The TCM can decode this information and determine the shift lever position. Each shift lever position has it own unique combination of closed and open switches. This is called a PRNDL code. There are 5 switches, therefore: there are many possible combinations of open and closed switches (codes). There are 12 valid codes, two for neutral, one for each other gear position (5), and five temporary (transition zone) codes. The remainder of the codes should never occur , these are called invalid codes.

45RFE/545RFE TRS SWITCH STATES

TRS	PARK	TMP1	REV	TMP 2	N1	N2	TMP 3	D	TMP4	2	TMP 5	L
T1 (C4)	OPEN	OPEN	OPEN	OPEN	OPEN	CLOSED	CLOSED	CLOSED	CLOSED	CLOSED	OPEN	OPEN
T2 (C5)	CLOSED	CLOSED	OPEN	OPEN	OPEN	OPEN	OPEN	OPEN	OPEN	CLOSED	CLOSED	CLOSED
T3 (C3)	OPEN	OPEN	OPEN	CLOSED	CLOSED	CLOSED	CLOSED	CLOSED	OPEN	OPEN	OPEN	CLOSED
T41 (C1)	CLOSED	OPEN	OPEN	OPEN	CLOSED	CLOSED	OPEN	OPEN	OPEN	OPEN	OPEN	OPEN
T42 (C2)	CLOSED	CLOSED	CLOSED	CLOSED	CLOSED	CLOSED	CLOSED	OPEN	OPEN	OPEN	OPEN	OPEN

DRBIII® REPORTED SHIFT LEVER ERROR CODES

ERROR CODE	SWITCH STUCK	POSITION
1	T41/C1 STUCK	OPEN
2	T41/C1 STUCK	CLOSED
3	T42/C2 STUCK	OPEN
4	T42/C2 STUCK	CLOSED
5	T3/C3 STUCK	OPEN
6	T3/C3 STUCK	CLOSED
7	T1/C4 STUCK	OPEN
8	T1/C4 STUCK	CLOSED
9	T2/C5 STUCK	OPEN
10	T2/C5 STUCK	CLOSED
11	OD LOCKOUT STUCK	OPEN
12	OD LOCKOUT STUCK	CLOSED

NOTE: If you are using the transmission simulator and do not push the OD off button in the vehicle when performing a Shift Lever position test, you will receive a code 11 OD lockout stuck open

Transmission Effects and Possible Causes:

(This code alone will not illuminate the MIL)

Excessive metal debris in the transmission oil pan
Worn Code Plate. Check for heavy wearing by TRS switch contacts
Intermittent C1 through C5 (T1, T2, T3, T41 or T42) circuits.
Check for corrosion, terminal push-outs or spread terminals at TCM connector and/or 23-way transmission connector.
TRS connector not plugged in, or unplugged with the key on.
TRS C1 through C5 (T1, T2, T3, T41, or T42) circuit(s) are open, shorted to ground, or shorted to 12 volts.
TRS
TCM

Name Of Code: P0124 (29) - Throttle Position Sensor/APPS Intermittent

P0122 (2A) - Throttle Position Sensor /APPS Low

P0123 (2B) - Throttle Position Sensor /APPS High

When Monitored: Engine speed > 500 RPM

Set Condition:

P0124 - Throttle angle change > 5° in 7 milliseconds the Fault set time milliseconds 0.448 seconds

P0122 - Throttle angle < 6° the Fault Set Time: 0.448 seconds

P0123 - Throttle angle > 120.6° the Fault Set Time: 0.448 seconds

Theory Of Operation: The Transmission Control Module (TCM) receives the throttle position signal from the Throttle Position Sensor (TPS). The TPS has a 5-volt pull up supplied from the Powertrain Control Module (PCM). The signal is checked for out-of-range as well as intermittent (excessive signal changes).

Transmission Effects: The MIL will illuminate, the transmission system will not go into limp-in mode. The TCM will use a "calculated throttle angle" supplied by the PCM over the communication bus. If the communication bus is unavailable, the TCM will use a default throttle angle of 24° degrees for the key start in which the code was set. The TCM will try to use the TPS signal again on the next key start. The vehicle may experience extremely erratic transmission shifting just prior to setting the code. If the intermittent does not last long enough to set the code, the customer will say that the transmission violently hunts between gears.

Possible Causes:

Open or shorted TPS signal and/or ground circuits
TCM connector problems
Failed TPS or TPS connector (Check PCM DTC's)
PCM
TCM

Name Of Code: P0944 (35) - Loss Of Prime

When Monitored: If the transmission is slipping in any forward gear and all the pressure switches are indicating no pressure, a loss of prime test is run.

Set Condition: If the transmission begins to slip in any forward gear, and all pressure switches are open, a loss of prime test begins. All available elements are momentarily turned on by the Transmission Control Module (TCM) to see if pump prime exists. The code is set if none of the pressure switches respond. The TCM will continue to run the loss of prime test until pump pressure returns.

NOTE: Loss of Prime test is not run when transmission temperature is "Super Cold".

Theory Of Operation: The loss of prime test is used to prevent transmission defaults, which can be caused by a lack of pump prime.

Transmission Effects: Vehicle will not move or transmission slips. Normal operation will continue if pump prime returns.

Possible Causes:

Low transmission fluid level
Transmission fluid filter improperly installed (Seal installed onto filter neck instead of into pump bore, seal not fully seated against pump bore housing, filter neck not engaged into pump, bolts loose or O-ring missing or damaged)
Transmission fluid filter clogged, damaged or cracked
Transmission has massive hydraulic leak (valve body pipe plugs missing, etc.)
Transmission oil pump
Transmission oil pump drive is sheared or damaged
PRNDL indicates a valid OD code in the hydraulic reverse position

Name Of Code: P1790 (36) - Fault Immediately After Shift

When Monitored: When a speed ratio error DTC (50 through 55) is stored.

Set Condition: This code is set if the associated speed ratio code is stored within 1.3 seconds after a shift.

Theory Of Operation: This code will only be stored along with a 50 series code. If this code is set, it indicates a probable hydraulic (line pressure) or mechanical problem exists. When this code is set, diagnosing the transmission should be based on the associated speed ratio code and mechanical causes should be considered first.

Transmission Effects: None

Possible Causes:

Mechanical causes as listed under associated speed ratio code.
Inadequate line pressure
Cut or damaged clutch piston seals

Name Of Code: P1775 (37) - Solenoid Switch Valve Latched in TCC Position

When Monitored: During an attempted shift into 1st gear.

Set Condition: This code is set if 6 unsuccessful attempts are made to get into 1st gear, with transmission temp above 27°C (80°F), in one given key start.

Theory Of Operation: The solenoid switch valve (SSV) controls the direction of the transmission fluid when the L-R solenoid is energized. The SSV will be in the downshifted position in 1st gear, thus directing the fluid to the L-R clutch circuit. In 2nd, 3rd, and 4th, it will be in the upshifted position and directs the fluid into the torque converter clutch (TCC).

When shifting into 1st gear, a special hydraulic sequence is performed to ensure SSV movement into the downshifted position. The L-R pressure switch is monitored to confirm SSV movement. If movement is not confirmed (the L-R pressure switch does not close), EMCC is inhibited until SSV operation is confirmed.

Transmission Effects: Transmission will have 1st gear and no EMCC operation. The MIL will illuminate after 5 minutes of no EMCC operation.

Possible Causes:

Valve body - Solenoid Switch Valve stuck in TCC position
L-R solenoid armature or plunger broken - should also set DTC P0841 (81) and often sets P0740 (38)
Solenoid malfunction - may also set code P0841 (81)
L-R Pressure Switch Sense circuit shorted to battery
High idle speed
PRNDL indicates a valid OD code in the hydraulic reverse position

Name Of Code: P0740 (38) - Torque Converter Clutch Control Circuit

When Monitored: During Electronically Modulated Converter Clutch (EMCC) Operation

Set Condition: The code will be set if one of the following events happens three times in a given key start, at a throttle angle less than 30°

With the transmission in EMCC, the TCC/L-R solenoid achieves the maximum duty cycle and is still unable to pull the engine speed within 60 RPM of input speed.
With the transmission in FEMCC, the TCC RPM (Engine speed - Input speed) is more than 100 RPM for 7.2 seconds.

Theory Of Operation: When in 2nd, 2nd Prime, 3rd, or 4th gear, the torque converter clutch (TCC) can be engaged when certain conditions are met. The TCC piston is electronically modulated by increasing the duty cycle of the L-R solenoid until the torque converter slip difference (difference between engine and transmission input speed) is within 60 RPM. Then the L-R solenoid is fully energized (FEMCC/100% duty cycle). Torque converter slip is monitored in FEMCC to ensure adequate clutch capacity.

Transmission Effects: EMCC will still be available after code is set. MIL will illuminate after 5 minutes of accumulated slip in FEMCC. The transmission will attempt normal operation (no limp-in) even after the MIL is illuminated.

Possible Causes:

Cut converter hub O-ring and/or failed torque converter - both should be replaced during a rebuild with code P0740 (38) present.
Sticky CC Regulator valve

Name Of Code: P1776 (47) - Solenoid Switch Valve (SSV) Latched in L-R Position

When Monitored: Continuously when doing partial or full EMCC (PEMCC or FEMCC)

Set Condition: If the transmission senses the L-R pressure switch closing while performing PEMCC or FEMCC. This code will be set after four unsuccessful attempts to perform PEMCC or FEMCC.

Theory Of Operation: The solenoid switch valve (SSV) controls the direction of the transmission fluid when the L-R solenoid is energized. SSV will be in the downshifted position in 1st gear, thus directing the fluid to the L-R clutch circuits. In 2nd, 3rd, and 4th, the SSV will be in the upshifted position and directs the fluid into the torque converter clutch (TCC).

When doing PEMCC or FEMCC, the L-R pressure switch should indicate no pressure if the SSV is in the TCC position. If the L-R pressure switch indicates pressure while in PEMCC or FEMCC, EMCC operation is aborted and inhibited to avoid inadvertent application of the L-R clutch. Partial EMCC will be attempted if the L-R pressure switch does not indicate pressure. Four occurrences of detection of L-R pressure results in setting the code.

Transmission Effects: EMCC is inhibited and the transmission system will default to the Orderly Shutdown routine. (this DTC can take up to five minutes of problem identification before illuminating the MIL)

Possible Causes:

Valve body - Solenoid Switch Valve stuck in L-R position
Intermittent short to ground or open circuit in L-R Pressure Switch Sense circuit (with code P0841 only)
Solenoid/TRS assembly (with code P0841 (81) only)
TCM (with code P0841 (81) only)

Name Of Code: P1793 (48) - Torque Reduction (TRD) Link Communication Error

When Monitored: During torque managed shifts (Throttle angle above 54 degrees). This system is also tested whenever the vehicle is stopped and the engine speed is below 1000 RPM.

Set Condition: This code is set when the Transmission Control Module (TCM) sends two subsequent torque reduction messages to the Powertrain Control Module (PCM) via the TRD link circuit and does not receive a confirmation from the PCM over the communication bus.

Theory Of Operation: During high torque shifts the TCM will send a message requesting that the PCM reduce engine power until the shift is completed. This message is sent from the TCM to the PCM across the Torque Management Request Sense Circuit. The PCM will acknowledge the TCM request by sending a confirmation message across the communication bus. The TRD Link communication is also tested periodically for operation whenever the engine is running and the vehicle is not moving with zero degrees throttle.

Transmission Effects: Maximum throttle angle used by TCM will be 54 degrees. As a result a customer may complain about loss of performance and/or normal and WOT shifts may be harsh.

Possible Causes:

Sticky Throttle Position Sensor (TPS)
Wiring or Connector problems in the Torque Management Request Sense Circuit
Bus communication problems.
PCM
TCM

Name Of Code: P0736 (50) - Gear Ratio Error in Reverse

P0731 (51) - Gear Ratio Error in 1st

P0732 (52)- Gear Ratio Error in 2nd

P0733 (53) - Gear Ratio Error in 3rd

P0734 (54) - Gear Ratio Error in 4th

P1736 (55) - Gear Ratio Error in 2nd Prime

P0715 (56) - Input Speed Sensor

P0720 (57) - Output Speed Sensor

P1794 (58) - Speed Sensor Ground

P0735 (59) - Gear Ratio Error in 4th Prime

When Monitored: The transmission gear ratio is monitored continuously while the transmission is in gear.

Set Condition: This code is set if the gear ratio is not correct for the current gear.

Codes 50 through 59 sets if the ratio of the input RPM (Nt) to the output RPM (No) does not match the current gear ratio.
Code 56 sets if there is an excessive change in input RPM in any gear
Code 57 sets if there is an excessive change in output RPM in any gear
Code 58 sets after a TCM reset in neutral and Nt/No equals a ratio of input to output of 2.00

Theory Of Operation: The transmission system uses two speed sensors, one to measure input RPM and one to measure output RPM. These inputs are essential for proper transmission operation. Therefore, the integrity of this data is verified through the following checks:

When in gear, if the gear ratio does not compare to a known gear ratio, the corresponding in-gear trouble code is set (codes 50 through 59).
An excessive change in input or output speeds indicating signal intermittent will result in codes 56 and/or 57 being set.
If the common speed sensor ground circuit is lost, both sensor inputs will read the signal from the input speed sensor at idle in neutral. Since the input speed sensor has 60 teeth and the output speed sensor has 30 teeth, this results in a ratio of 2.00.

Transmission Effects: If a gear ratio error develops, the appropriate code is set as a one trip failure and the 5 minute Intelligent Recovery Timer (IRT) is started. The transmission will then substitute a 1-3 or 3-1 shift to a different gear for the one in which the problem was identified. For example, if a problem is identified while in first gear, the transmission will shift to third gear. The IRT is only counting up while the transmission is substituting one gear for another. Using the previous example, if the vehicle continued down the road and shifted to fourth gear for a long period of time, the IRT would have only counted the time that the transmission was in third gear instead of second. The MIL will illuminate (this DTC can take up to five minutes of problem identification before illuminating the MIL). The transmission system will default to the Logical Shutdown (without recovery) routine after 5 minutes of substituted gear operation or if three gear ratio error events occur in a given key start.

Possible Causes: Code P0736 (50) - Excludes gear train failures which should be obvious upon disassembly

If code P0944 (35) or any line pressure DTC's are set, diagnose these first
Valve body - #3 check ball
L-R switch valve sticking - may also set code P0731 (51)
Speed sensor or associated wiring - may also set codes P0731 (51), P0715 (56), or P0720 (57)
Multi Select Solenoid sticking or leaking
Failed or slipping L-R clutch - may also set code P0731 (51)
- L-R seal leakage (Intermittent no drive or reverse)
- Sticky L-R accumulator seals (Intermittent no drive or reverse)
Failed reverse clutch (hard code)
- OD/Rev lip seal leakage
- Worn reaction shaft support seal rings
Code P0731 (51) - Excludes gear train failures which should be obvious upon disassembly
1. If code P0944 (35) or any line pressure DTC's are set, diagnose these first
2. Valve body - #1, #2, and/or #4 check ball
3. L-R switch valve sticking
4. Speed sensor or associated wiring - may also set codes P0736 (50), P0715 (56), or P0720 (57)
5. Solenoid/TRS assembly (stuck solenoid(s))
6. Failed or intermittent slipping UD clutch - may also set P0732 (52) or P0733 (53)
  - UD seal leakage
  - Sticky UD accumulator seals
  - Worn reaction shaft support seal rings
7. Failed or slipping L-R clutch - may have code P0736 (50)
  - L-R seal leakage
  - Sticky L-R accumulator seals
Code P0732 (52) - Excludes gear train failures which should be obvious upon disassembly
1. If code P0944 (35) or any line pressure DTC's are set, diagnose these first
2. Valve body - #1, #2, #4, #5 and/or #7 check ball
3. Solenoid/TRS assembly - may also set codes P0846 (54) and/or P0845 (A2)
4. Failed or slipping 2nd clutch
  - 2nd clutch seal leakage
  - Sticky 2nd clutch accumulator seals
5. Failed or intermittent slipping UD clutch - may also set code P0731 (51) and/or P0733 (53)
  - UD clutch seal leakage
  - Worn input hub bushing
  - Sticky UD clutch accumulator seals
  - Worn reaction shaft support seal rings
Code P0733 (53) - Excludes geartrain failures which should be obvious upon disassembly
1. If code P0944 (35) or any line pressure DTC's are set, diagnose these first
2. Valve body - #1, #2, and/or #6 check ball
3. Speed sensor or associated wiring - may also set codes P0736 (50), P0715 (56), or P0720 (57)
4. Solenoid/TRS assembly - may also set codes P0871 (84) and/or P0870 (A4)
5. Failed or slipping OD clutch - may also set code P0734 (54)
  - OD clutch inner and outer lip seal leakage
  - Sticky OD clutch accumulator seals
  - Worn reaction shaft support seal rings
6. Failed or intermittent slipping UD clutch - may also set codes P0731 (51) and/or P0732 (52)
  - UD seal leakage
  - Worn input hub bushing
  - Sticky UD clutch accumulator seals
  - Worn reaction shaft support seal rings
Code P0734 (54) - Excludes gear train failures which should be obvious upon disassembly
1. If code P0944 (35) or any line pressure DTC's are set, diagnose these first
2. Valve body - #1, #2, #5 and/or #6 check ball
3. Speed sensor or associated wiring - may also set codes P0736 (50), P0715 (56), or P0720 (57)
4. Solenoid/TRS assembly - may also set codes P0988 (88) and/or P0987 (A8)
5. Failed or slipping OD clutch - may also set code P0733 (53)
  - OD clutch inner and outer lip seal leakage
  - Sticky OD clutch accumulator seals
  - Worn reaction shaft support seal rings
6. Failed or intermittent slipping 4th clutch
  - 4th clutch seal leakage
  - Sticky 4th clutch accumulator seals
  - Worn reaction shaft support seal rings
Code P1736 (55) - Excludes gear train failures which should be obvious upon disassembly
1. If code P0944 (35) or any line pressure DTC's are set, diagnose these first
2. Valve body - #1, #4 and/or #5 check ball
3. Speed sensor or associated wiring - may also set codes P0736 (50), P0715 (56), or P0720 (57)
4. Solenoid/TRS assembly - may also set codes P0876 (90) and/or P0875 (B0)
5. Failed or intermittent slipping UD clutch - may also set codes P0731 (51) and/or P0732 (52)
  - UD seal leakage
  - Worn input hub bushing
  - Sticky UD clutch accumulator seals
  - Worn reaction shaft support seal rings
6. Failed or intermittent slipping 4th clutch
  - 4th clutch seal leakage
  - Sticky 4th clutch accumulator seals
  - Worn reaction shaft support seal rings
Codes P0715 (56) and P0720 (57)
1. Failed input or output speed sensor
2. Shorted or open wiring between TCM and speed sensor(s)
3. Connector problems at TCM connector and/or speed sensor connector(s)
4. Transmission Solenoid /TRS Assembly has an internal short to the Speed Sensor Ground circuit (should also set a P1794).
  Code P1794 (58)
5. Open or shorted speed sensor ground (speed sensor ground is different from chassis ground)
6. Open or shorted Temperature Sensor wiring to TRS
7. Transmission Solenoid /TRS Assembly has an internal short to the Speed Sensor Ground circuit
8. TRS
9. TCM

Code P0735 (59) - Excludes gear train failures which should be obvious upon disassembly

If code P0944 (35) or any line pressure DTC's are set, diagnose these first
These codes may also be set with the DTC - P1790 (36), P0846 (82), P0871 (84), P0845 (A2), P0870 (A4), perform these diagnostics first.
Speed sensor or associated wiring - may also set codes P0736 (50), P0715 (56), or P0720 (57)
Solenoid/TRS assembly (stuck solenoid(s))
Failed or slipping OD clutch
OD seal leakage
Failed or slipping 2C clutch
2C seal leakage

Name Of Code: P2700, P2701, P2702, 2703, 2704 (60, 61, 62, 63, 64) - Inadequate Element Volume

When Monitored: Whenever the engine is running, the clutch volume is updated during the requested shift.

Set Condition:

NOTE: Transmission temperature must be 43°C (110°F) to update all volumes.

P2700 - When the LR volume falls below 16, the LR volume is updated during a 3-1 or 2-1 manual downshift with the TPS angle below 5 degrees.
P2701 - When the 2C volume falls below 5, the 2C volume is updated during a 3-2 kickdown with the TPS angle between 10 and 54 degrees.
P2702 - When the OD volume falls below 6, the OD volume is updated during a 2-3 upshift with the TPS angle between 10 and 54 degrees.
P2703 - When the UD volume falls below 11, the UD volume is updated during a 4-3 kick-down with the TPS angle between 30 and 54 degrees.
P2704 - When the 4C volume falls below 30, the 4C clutch volume is updated when doing a 3-4 shift with throttle angle between 10° and 54°. The transmission temperature must be above 43 C (110°F). The clutch volume should be between 30 and 85.

Theory Of Operation: The volumes of the transmission fluid needed to apply the friction elements are continuously monitored and learned for adaptive controls. As the clutch friction material wears, the volume of fluid needed to apply the clutch increases. The following are typical clutch volumes, the clutches may be damaged if the volumes are greater or less than the specified below:

2C clutch volume - between 25 and 85

OD clutch volume - between 30 and 100

4C clutch volume - between 30 and 85

UD clutch volume - between 30 and 100

Transmission Effects: These codes usually set with other DTC's, which indicates an internal transmission problem.

Possible Causes:

Clutch pack clearance out of spec
Snap ring out of position or broken
Broken return spring
Hydraulic leak into clutch circuit with near-zero volume

Name Of Code: P1715 (65) - Restricted Port in T3 Range

When Monitored: Whenever the Engine is running and the Manual valve is in the T3 range.

Set Condition: The code is set if the conditions for a code 47 are present when the manual valve is in the T3 range.

Theory Of Operation: The conditions to set a DTC 47 are easily satisfied while in the T3 range. There is no problem with the transmission itself if this code is set.

Transmission Effects: The transmission will go into neutral when this code is set. If the driver puts the shifter in neutral and back to drive, the transmission will operate normally.

Possible Causes:

Manual linkage out of adjustment, causing T3 range while shifter is in OD.
Driver resting hand on shift lever while driving, causing T3 range.

Name Of Code: P0218 (75) - High Temperature Operation Activated

When Monitored: Whenever the engine is running.

Set Condition: Immediately when the Overheat shift schedule is activated.

Theory Of Operation: If the transmission oil temperature rises above 116°C (240°F), the overheat shift schedule is activated, refer to the TRANSMISSION OPERATION AND SHIFT SCHEDULING AT VARIOUS OIL TEMPERATURES . The code is an information code only and is being set to aid the technician in determining root cause of a customer driveability issue. The code is also intended to alert the technician to determine if a cooling system malfunction has occurred or if an additional transmission air to oil cooler should be added to the vehicle if the customer regularly drives in a manner that overheats the transmission. Extended operation above 116°C (240°F) will reduce the durability of the transmission and should be avoided. Correcting the cooling system malfunction or installing an additional transmission oil cooler will improve transmission durability especially for customers who operate in city/construction stop and go traffic, tow trailers regularly, drive aggressively in low gear or drive regularly in mountainous areas.

Transmission Effects: Information only code. - Overheat shift schedule was activated, no limp-in condition occurs. See description of overheat shift schedule.

Possible Causes:

Transmission Overfilled with Oil
Engine cooling fan failure
Engine thermostat stuck closed
Radiator corroded or packed with dirt
Transmission cooler corroded or packed with dirt
Transmission fan not functioning properly
Transmission Oil Cooler Plugged
Customer driving pattern requires additional transmission cooling

Name Of Code: P0884 (76) - Power-Up at Speed

When Monitored: When TCM (Transmission Control Module) initially powers-up.

Set Condition: If the TCM powers up and senses a valid forward gear PRNDL code and the output RPM is above 800 RPM approx. 32 km/h (20 MPH) the code will be set.

Theory Of Operation: If a vehicle loses power to the TCM, the solenoids will go to their respective power off state. Some solenoids are normally vented and some are normally applied in their power off state. The transmission is designed to be in 3rd gear with all of the solenoids in this state. However, if power is restored, the TCM will power-up and normal operation will be restored.

This code identifies that power to the TCM was restored when the gear selector was in a "Drive" position while the vehicle was moving at speeds above 32 km/h (20 MPH). This code does not indicate a problem with the transmission or TCM, instead, it suggests intermittent problems in the fused ignition switch output, fused B(+), or ground circuits to the TCM. Alternately, if a person performs a rolling restart maneuver, the code can be set. Therefore it is critical that this DTC be investigated if the vehicle is experiencing intermittent 3rd gear operation and a subsequent return to normal operation.

Transmission Effects: No limp-in, although the symptom might be described as an intermittent limp-in. Code is for information only when trying to diagnosis intermittent 3rd gear operation and a subsequent return to normal operation.

Possible Causes:

No Problem if vehicle is started in "neutral" at speeds above 32 km/h (20 MPH) and shifted quickly to a forward gear position.
Quick key off then on while driving is any forward gear.
FOR INTERMITTENT 3rd GEAR OPERATION AND THEN A SUBSEQUENT RETURN TO NORMAL OPERATION WITHOUT CYCLING THE IGNITION KEY
Intermittent Direct Battery (Fused B+) connection between TCM (60-way pin 56) and battery.
Intermittent Fused Ignition Switch Output between TCM (60-way pin 11) and ignition switch.
Intermittent Ground to TCM (60 way pins 53 and 57).

Name Of Code: P0890 (80) - Switched Battery

When Monitored: Ignition key is turned from "off" position to "run" position and/or ignition key is turned from "crank" position to "run" position.

Set Condition: This code is set if the Transmission Control Module (TCM) senses voltage on any of the pressure switch inputs prior to the TCM energizing the relay.

Theory Of Operation: The Transmission control relay is used to supply power to the solenoids and pressure switches when the transmission is in normal operating mode. When the relay is off, no power is supplied and the transmission is in "limp-in" mode. The relay output is fed back to the TCM through pins 16, 17 and 38. It is referred to as "Transmission Control Relay Output".

Immediately after a controller reset (ignition key turned to the "run" position or after cranking engine), the TCM verifies that the relay contacts are open by checking for no voltage at the transmission control relay output terminals. After this is verified, the voltage at the pressure switches is checked. There should be no voltage on the pressure switches at this time. The TCM will then activate the relay.

Transmission Effects: The MIL will illuminate and the transmission system will default to the Immediate Shutdown routine.

Possible Causes:

Short to battery on one or more pressure switch sense circuits.
TCM connector problems.
Solenoid/TRS connector problems.
TCM.

Name Of Code: P0841 (81) - LR Pressure Switch Sense Circuit

P0846 (82) - 2C Pressure Switch Sense Circuit

P0871 (84) - OD Pressure Switch Sense Circuit

P0988 (88) - 4C Pressure Switch Sense Circuit

P0876 (90) - UD Pressure Switch Sense Circuit

When Monitored: Whenever the engine is running.

Set Condition: The appropriate code is set if one of the pressure switches are open or closed at the wrong time in a given gear (see chart below).

Theory Of Operation: The Transmission system uses five pressure switches to monitor the fluid pressure in the LR, 2C, 4C, UD, and OD clutch circuits. The pressure switches are continuously monitored for the correct states in each gear as shown below.

45RFE/545RFE NORMAL PRESSURE SWITCH STATES

GEAR	L/R	2C	4C	UD	OD
R	OPEN	OPEN	OPEN	OPEN	OPEN
N	CLOSED	OPEN	OPEN	OPEN	OPEN
1ST	CLOSED	OPEN	OPEN	CLOSED	OPEN
2ND	OPEN	CLOSED	OPEN	CLOSED	OPEN
2 PRIME	OPEN	OPEN	CLOSED	CLOSED	OPEN
3RD	OPEN	OPEN	OPEN	CLOSED	CLOSED
4TH	OPEN	CLOSED	CLOSED	OPEN	CLOSED
4 PRIME	OPEN	OPEN	OPEN	OPEN	CLOSED

NOTE: L/R PRESSURE SWITCH OPENS ABOVE 150 OUTPUT RPM IN 1ST GEAR AND CLOSES BELOW 100 OUTPUT RPM.

Transmission Effects: The MIL will illuminate and the transmission system will default to the Immediate shutdown routine.

Possible Causes:

If code P0944 (35) is present, perform code P0944 (35) diagnostic procedures
Transmission fluid filter improperly installed (Seal installed onto filter neck instead of into pump bore, seal not fully seated against pump bore housing, filter neck not engaged into pump, bolts loose or O-ring missing or damaged)
Reverse carrier snap ring dislodged (typically sets on heavy throttle acceleration from a dead stop)
Pressure switch sense circuit open or shorted to ground between TCM and Solenoid/TRS assembly
Pressure switch sense circuit shorted to battery
Pressure switch
Loose valve body bolts
Plugged filter - internal transmission or torque converter failure
Check ball not seating or damaged.
Solenoid malfunction (If set with corresponding Solenoid DTC. Ie: 2C Pressure switch set with 2C solenoid)
Oil Pump (Code P0841 (81) only)
TCM

Name Of Code: P0845 (A2) - 2C Hydraulic Pressure Test Failure

P0870 (A4) - OD Hydraulic Pressure test failure

P0987 (A8) - 4C Hydraulic Pressure test failure

P0875 (B0) - UD Hydraulic Pressure test failure

When Monitored: In any forward gear with engine speed above 1000 RPM shortly after a shift and every minute thereafter.

Set Condition: Immediately after a shift into a forward gear, with engine speed above 1000 RPM, the TCM momentarily turns on element pressure to the clutch circuits that do not have pressure to identify that the appropriate pressure switch closes. If the pressure switch does not close it is tested again. If the switch does not close the second time, the appropriate code is set.

Theory Of Operation: The Transmission Control Module (TCM) tests the pressure switches when they are off. The test verifies that the switches are operational (They will close with pressure applied). The TCM verifies that the switch closes when the corresponding element is applied. If a switch fails to close, it is re-tested. If it fails the second test, the code is set.

Transmission Effects: The MIL will illuminate and the transmission system will default to the orderly Shutdown routine

Possible Causes:

Line Pressure Sensor
Pressure switch sense circuit shorted to battery between TCM and solenoid/TRS assembly.
Solenoid malfunction (If set with corresponding Solenoid DTC. Ie: 2C Hydraulic Pressure switch set with 2C solenoid)
Low oil pressure
Pressure switch

Name Of Code: P0750 (C1) - LR Solenoid Circuit

P0755 (C2) - 2C Solenoid Circuit

P0760 (C3) - OD Solenoid Circuit

P0770 (C4) - 4C Solenoid Circuit

P0765 (C5) - UD Solenoid Circuit

P2706 (C6) - MS Solenoid Circuit

When Monitored: Initially at power-up, then every 10 seconds thereafter. They will also be tested immediately after a gear ratio or pressure switch error is detected.

Set Condition: Three consecutive solenoid continuity test failures, or one failure if test is run in response to a gear ratio or pressure switch error.

Theory Of Operation: Six solenoids are used to control the friction elements (clutches). The continuity of the solenoid circuits are periodically tested. Each inactive solenoid is turned on for a few milliseconds, then off. Each active solenoid is turned off for a few milliseconds, then on. This pulsing of voltage to the solenoid causes an inductive spike which can be sensed by the TCM. If an inductive spike is not sensed by the Transmission Control Module (TCM) during the continuity check, it is tested again. If the test fails three consecutive times, the appropriate code is set. If the solenoid test is run in response to a gear ratio or pressure switch error, one failure will result in setting the appropriate code.

Transmission Effects: The MIL will illuminate and the transmission system will default to the Immediate Shutdown routine.

Possible Causes:

Open or shorted solenoid circuit(s) between TCM and solenoid/TRS assembly.
Open ground circuit.
TCM connector problems.
Solenoid/TRS connector problem.
Solenoid/TRS assembly.
TCM

Name Of Code: P0711 (7A) - Transmission Temperature Sensor Performance

When Monitored: Every 7 milliseconds with the engine running and no loss of prime DTC set.

Set Condition: A temperature reading of 80°F is not reached in the specified period of time

Theory Of Operation: The temperature sensor (thermistor) is used to sense the temperature of the transmission fluid. Transmission fluid temperature can affect shift quality, torque converter lock-up, and when and if some diagnostics are run. A failed temperature sensor could affect the OBD II diagnostics, therefore when a fault is detected in the temperature sensor circuit, transmission temperature will be based on a calculated temperature value.

Transmission Effects: When the fault is set, calculated temperature is substituted for measured temperature, however the fault code is stored only after three consecutive occurrences of the fault.

Possible Causes:

Temperature sensor

Temperature sensor wiring circuit.

Internal controller

Name Of Code: P0712 (7B) - Transmission Temperature Sensor Low

When Monitored: Every 7 milliseconds with the engine running and no loss of prime DTC set.

Set Condition: Sensor output voltage less than 0.078v.

Transmission Effects: When the fault is set, calculated temperature is substituted for measured temperature, however the fault code is stored only after three consecutive occurrences of the fault.

Possible Causes:

Temperature sensor

Temperature sensor wiring circuit.

Internal controller

Name Of Code: P0713 (7C) - Transmission Temperature Sensor High

When Monitored: Every 7 milliseconds with the engine running and no loss of prime DTC set.

Set Condition: Sensor output voltage greater than 4.94v.

Transmission Effects: When the fault is set, calculated temperature is substituted for measured temperature, however the fault code is stored only after three consecutive occurrences of the fault.

Possible Causes:

Temperature sensor

Temperature sensor wiring circuit.

Internal controller

Name Of Code: P0714 (7D) - Transmission Temperature Sensor Intermittent

When Monitored: Every 7 milliseconds with the engine running and no loss of prime DTC set.

Set Condition: Temperature reading change greater than maximum change allowed per loop.

Transmission Effects: When the fault is set, calculated temperature is substituted for measured temperature, however the fault code is stored only after three consecutive occurrences of the fault.

Possible Causes: Temperature sensor Temperature sensor wiring circuit.

Internal controller

Name Of Code: P0868 (C9) - Line Pressure Low; P0869 (CB) - Line Pressure High

P0932 (CA) - Line Pressure Sensor Circuit Fault

P0934 (CC) - Line Pressure Sensor Low

P0935 (CD) - Line Pressure Sensor High

When Monitored (P0932): Continuously while driving in a forward gear.

Set Condition: The TCM continuously monitors transducer Line Pressure Output and compares it to Desired Line Pressure. If the difference between transducer Line Pressure output and Desired Line Pressure is 10 PSI or greater, the DTC will set in approximately 3.57 seconds.

When Monitored (P0934): Continuously with engine running and Output Speed greater than 390 RPM.

Set Condition: This DTC will set when the Line Pressure Sensor output is less than 0.35 volts for 1.4 seconds.

When Monitored (P0935): Continuously with engine running, Output Speed greater than 390 RPM and Desired Line Pressure less than 200.

Set Condition: This DTC will set if is Line Pressure Sensor Output is greater than 4.75 volts for 1.4 seconds.

When Monitored (P0868): Continuously while driving in a forward gear.

Set Condition: The TCM continuously monitors transducer Line Pressure Output and compares it to Desired Line Pressure. If transducer Line Pressure Output is more than 10 PSI below Desired Line Pressure, the DTC will set in approximately 2.1 seconds.

When Monitored (P0869): Continuously while driving in a forward gear.

Set Condition: The TCM continuously monitors transducer Line Pressure Output and compares it to Desired Line Pressure. If transducer Line Pressure Output is more than 10 PSI above Desired Line Pressure, the DTC will set in approximately 3.57 seconds.

Theory Of Operation: Line pressure is controlled by the TCM. It is measured by the Line Pressure Sensor (LPS) and regulation is achieved by changing the duty cycle of the Pressure Control Solenoid (PCS). (5% duty cycle = solenoid off = max line pressure, 62% duty cycle = solenoid on = min line pressure). The TCM calculates the desired line pressure based on inputs from the transmission and engine. The TCM calculates torque input to the transmission and uses it as the primary input to the desired line pressure calculation. This is called Torque Based Line Pressure. In addition, the line pressure is set to a preset level 827 or 931 kPa (120 or 135 PSI) during shifts and in Park and Neutral to ensure consistent shift quality. The desired line pressure is continuously being compared to the actual line pressure. If the actual line pressure is consistently higher than the target, the line pressure high DTC P0869 (CB) will be set. If the actual line pressure is consistently lower than the target, the line pressure low DTC P0868 (C9) will be set. If it is consistently out of range, but not consistently high or low, it is considered out of range and the line pressure error DTC P0932 (CA) will be set.

Transmission Effects: The Transmission system will default to open loop line pressure control resulting in a fixed PCS duty cycle. This duty cycle will change slightly depending on temperature and current gear.

Possible Causes:

Sticking Regulator Valve
Pressure Control Solenoid
Line Pressure Sensor.
Oil pump
Plugged Filter
5V supply circuit to Line Pressure Sensor open (Sensor reading will display a constant value between 586 and 655 kPa (85 and 95 PSI)
LPS signal circuit shorted to ground, shorted to voltage, or open.
5-volt supply circuit shorted to ground, shorted to voltage, or open.
Open sensor ground
TCM